Ground effect machine equipped with auxiliary selectively adjustable ground engaging ropelling mechanisms



July 2, 1963 w. R. BERTELSEN 3,095,938

GROUND EFFECT MACHINE EQUIPPED WITH AUXILIARY SELECTIVELY ADJUSTABLE GROUND ENGAGING PROPELLING MECHANISMS Filed Dec. 3, 1959 4 Sheets-Sheet 1 Fig.1.

INVENTOR.

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GROUND EFFECT MACHINE EQUIPPED WITH AUXILIARY SELECTIVELY ADJUSTABLE GROUND ENGAGING PROPELLING MECHANISMS Filed Dec. 3, 1959 4 Sheets-Sheet 2 INVENTOR:

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GROUND EFFECT MACHINE EQUIPPED WITH AUXILIARY SELECTIVELY ADJUSTABLE GROUND ENGAGING PROPELLING MECHANISMS Filed Dec. 3, 1959 4 Sheets-Sheet 5 INVENTOR:

July 2, 1963 w. R. BERTELSEN 3,095,938

GROUND EFFECT MACHINE EQUIPPED WITH AUXILIARY SELECTIVELY ADJUSTABLE GROUND ENGAGING PROPELLING MECHANISMS 4 Sheets-Sheet 4 Filed Dec. 5, 1959 INVENTOR? ZM Jl/iam Z2 Berzfalsen/ Qrziipei fig. 10.

United States Patent GROUND EFFECT MACHINE EQUIPPED WITH AUXILIARY SELECTIVELY A D J U S T A B L E GRGUND ENGAGING PROPELLING MECHA- NESMS William R. Bertelsen, Neponset, Ill., assignor, by direct and mesne assignments, of twenty-five percent to William E. Martin, Kewanee, BL, and twenty-five percent to Martin Engineering Company, Neponset, Ill., a corporation of Hlinois Filed Dec. 3, 1959, Ser. No. 857,212

1 Claims. (Cl. 18(l'7) This invention relates to an improvement in the construction of a gas sustained vehicle of the character set forth and described in my copending application Serial No. 731,001, filed April 25, 1958, entitled Vehicle.

More specifically, this invention is directed to a retractable propulsion means for an aeromobile comprising the embodiment of auxiliary drive mechanisms which are power driven tracks that provide supplemental or substitute actuating means functioning to move an air supported and air directed vehicle over a reaction surface that is being traversed or negotiated by such a vehicle.

One of the objects of the invention is to provide a supplemental drive mechanism for a vehicle that is normally airborne by a reactionary air or gas cushion created by the vehicle and which renders the vehicle dirigible either adjacent to or remote from a reaction surface.

An aeromobile vehicle of this character is most efiicient and maneuverable over a generally level surface under relatively reasonable motive power to create the pressurized air for sustaining this vehicle and for use with suitable flap controls to guide such a vehicle. How ever, for heavy pulling and for negotiating steeper grades, other power drive means are desirable and needed to render the air vehicle more efficient and more versatile in its operation.

It is, therefore, another object of this invention to embody auxiliary drive mechanisms into an aeromobile for operation under adverse conditions such as those mentioned above to motivate and to extend the maneuverability of such a vehicle.

Another object of the auxiliary drive means is to mount such means upon the air carried vehicle for selective displacement and use or non-use between operative and inoperative positions with respect to the vehicle itself.

A further object is to provide an auxiliary drive means which is constructed and arranged similarly to the air track disclosed and described in my copending application Serial No. 857,213, filed of even date herewith and since issued as Patent No. 3,074,764.

Other objects and advantages inherent in the construction of the auxiliary propulsion means for an aeromobile and in the new combinations developed through the use thereof shall hereinafter appear in or become evident from the following detailed description having reference to the accompanying drawings forming a part of this specification.

In the drawings:

FIG. 1 is a side elevational view of an air vehicle embodying the auxiliary propulsion means of this invention, the near side of the unit omitting the propulsion means to better view the far side drive structure and its relationship to the vehicle per se when disposed in operative position;

FIG. 2 is a front elevational View of the entire vehicle assembly with the drive means in operative position;

FIG. 3 is a plan view of the vehicle with the auxiliary drive means shown as lowered and in active operative position to propel the vehicle;

FIG. 4 is an inside or vehicle side elevational view of the right hand track of the vehicle in FIG. 3 with parts thereof broken away and shown in section;

FIG. 5 is a diagrammatic cross sectional view of the pressurized air source mechanism of the air operated vehicle including added duct and air supply means to direct air under pressure to the drive arrangement provided as air tracks;

FIG. 6 is a fragmentary vertical cross sectional view of a portion of the auxiliary air track propulsion means to show certain details of construction thereof;

FIG. 7 illustrates a modified construction of drive mechanism to show another manner of suspension in the adaptation of the power drive means and its association with an air driven vehicle;

FIG. 8 illustrates a side elevational view of another modified vehicle with a combination structure providing an air sustained apparatus having retractable auxiliary track assemblies that furnish positive ground engaging propulsion means when desired or necessary for moving a vehicle of this type, this arrangement including vehicle air dispersion upon the track units for enhancing the tractive efiort of the tracks and to eliminate the necessity of using other track stabilizing mechanisms;

FIG. 9 is a cross sectional view taken along a. vertical plane substantially coincident with the line 99 in FIG. 8 illustrating the track assemblies as they appear when in use as shown in full lines, the retractable positions thereof being indicated in broken lines at each side of the air type vehicle; and

FIG. 10 is a front end view of the vehicle to show one means for supplying the drive to the track assemblies by means of a power unit connected through transmission units and flexible drive cables to at least one drive wheel of each track.

The air vehicle is best shown in FIGS. 1, 2, and 3 comprising, generally, a framework 1 to support a blower 2 that includes a fan 3 driven by a motor or engine 4 to direct pressurized air into chambers 5 and 6, etc., providing means to discharge the air downwardly about the periphery of the mobile vehicle to float the latter in the manner described in my copending application, Serial No. 731,001. Fore and aft flaps 7 and 8 together with pairs of side flaps 9 and 10 provide control surfaces to steer the vehicle or to cause it to move bodily in selected directions. An operators seat 11 and a control 12 are provided at the front end of the vehicle, a gas tank 13 at the rear, and side frames 14 and 15 flank the main frame 1, while skids 16 and 17 form supporting rails for the vehicle when at rest in inoperative position upon the ground or upon some other supporting surface.

Under normal generally level terrain, the vehicle will scoot or glide as directed across a surface. If hard pulling is encountered or a steep incline is to be traversed, the vehicle is provided with auxiliary propulsion drive means 18 and 19 that can be stored in inoperative positions or lowered to operative ground engaging positions.

The drive means 18 and 19 each comprise an air track 20 of a flexible cleated belt or tread 21 that encircles an air box or plenum 22 and a drive wheel 23 to actuate the tread. Each track 20 is supported for swingable movement in relation to the air vehicle structure for operation between stored inoperative positions and lowered operative positions to support the vehicle for track motivation by physical contact of the tread 21 with an underlying surface.

The swinging arrangement for each track comprises fore and aft brackets 24 and 25 pivoted upon stub shafts 26 and?! mounted on brackets 28 and 29 on the side frames 14 and 15. Power cylinders 30 and 31 are employed to raise and lower the track assembly in relation to the vehicle per se.

The air tracks are driven by any suitable prime mover. In FIG. 3, an engine or motor 32 drives a suitable dual transmission 33 that provides drive shafts 34 and 35. Shaft 34' drives a telescopic splined shaft 36 through a universal 37 to transmit the drive to shaft 38 through a universal 39, and shaft 3% rotates the track drive wheel 23' of the track.

The auxiliary drive means are each simple and of light weight construction while operable under minimum frictional effort as described in tiny copending application Serial No. 857,213. The tracks require air under pressure for smooth and efiicient operation. While the air under pressure may be supplied by any suitable means, the construction shown provides an arrangement that is adapted for the conversion of the vehicle power blower for use as an air source for the tracks.

Generally, and as diagrammatically shown in PEG. 5, any cut-off or valving means such as a slidable baffle 41 will act to cut off the primary or first conduit means such as ducts or chambers 5 and 6 and which will ciose the exhaust portion of the blower chamber 42 from said conduit means to build up the air pressure in this chamber. Air' bleed outlets 43 and 44 deliver air under pressure through valves 45 and 4.6 to a second conduit means comprising, for example, conduits 47 and-4% that connect with thetrack plenurns 22.

Air then discharges out of the plenum 22 through vents or openings 49 into the area or space lying between the interior surface of the tread 21 and the peripheral face of the plenum 22 that lies adjacent to the interior tread surface whereby the air acts to urge said respective coacting plenum and tread members out of physical contact with respect to each other to provide an air cushion in the area between the described relatively movable members. 7

It is also contemplated to employ swingable air cushion tracks that incorporate power units within the track loops for independent individual operation of each track. Such an arrangement is disclosed and described in greater detail in my copending application Serial No. 857,214, filed of even date herewith and directed to a Self Propelled Vehicle Track and since issued as Patent No. 3,074,499.

FIG. 7 illustrates a modified form of auxiliary propulsion track. Here track 50 includes the plenum or air box 51 having brackets 52 and 53 to pivotally carry parallel links 54 and 55 that are carried on spaced brackets 56 and 57 mounted upon a wall member 58 of the vehicle 59. Power cylinders such as 60 regulate the track elevation for selective displacement between inoperative and operativepositions. 7

Referring now to FIGS. 8 to 10, the embodiment there shown, provides another arrangement wherein the air cushion vehicle can be rigged for positive ground contacting track propulsion when desired or when necessary under heavy pull and for negotiating steeper grades or excessively irregular terrain. By incorporating a positive ground engaging drivemeans, the vehicle operation is greatly broadened resulting in extended maneuverability of action.

In FIGS. 8 to 10, the vehicle or machine 61 comprises a chassis 62 having a frame 63 with a platform 64, with a suitable motor 65 mounted upon the platform to drive an air moving propeller 66. The motor and propeller are housed in a turret air cell 67 having an inlet throat 6S and a discharge base 69 to radially distribute pressurized air into the platform air cell 70 provided with conduit 'means for normal distribution of air out of the exhaust ground. This action normally sustains the vehicle or machine under the ground effect principle. Flap valves 75, 76, 77 and 78 are suitably joined with control means for regulation by an operator to maneuver the vehicle by air control discharge according to the selected positions occupied by the flap valves in relation to the ducts and to the machine. Fore and aft pairs of skids 79 and 89 are connected with the. chassis 62. to provide means to normally support the machine in stopped position and under air cut-off conditions.

The retractable propulsion means of the vehicle or machine 61 comprises track assemblies 81 and 82 connected with the machine at the opposite sides thereof. Each track assembly comprises a flexible track or belt 83 looped at its ends over fore and aft wheels 84 and 85 located at the leading and trailing ends of the machine.

Stub shafts 86 and 87 are connected with the wheels 84 and 35 while brackets 88 and 89"rotatably carry the shafts S6 and 87 and are secured to opposite ends of side shafts S t} and 91 flanking the machine sides. Duplicate sets of bearing brackets 92, 93 and 94' are mounted on opposite sides of the chassis 62' to support each of the shafts 9i! and 91 respectively for rotation, while rotation of the shafts causes each wheel and track assembly 81 and 82 to swing between the full line and broken line positions best shown in FIG. 9.

Individual power cylinders such as 95 are carried transversely of the chassis and are mounted upon opposite sides upon platform 64 with each cylinder having its ram connected with one of the brackets such as 96 that are fastened to the shafts 9t) and 91 respectively to provide the means to freely rock each shaft for swinging the track assemblies 31 and 82 as shown in FIG. 9. Obviously suitable power means may be employed to actuate both shafts 90 and 91 in unison, if desirable, to obtain a concerted action of swing of the track units between raised stored inoperative and lowered operative positions.

FIG. 10 demonstrates one exemplary arrangement that can be employed to drive the track assemblies. An engine or motor 97 driving a shaft 98 that transmits power to speed changers 99 and 100. Flexible cables 101 and 102 carry suitable flexible drive mechanisms 103 that connect with worm and worm wheel units 104 and 105 connected to drive shafts 86 that in turn drive track drive wheels 84. Each drive mechanism 103 is mounted for stability by means of brackets 1% that fixedly mount upon the front wheel brackets 8-8. Speed changers 99 and have suitable control levers 107 and 108 to drive the track assemblies individually or in unison to maneuver the machine in the usual fashion.

When the wheel units are lowered, each flexible track 83 assumes a position underlying the exhaust side ducts 73 and 74. Thus by closing the end duct flaps or flap valves 75 and 76 to concentrate air discharge into the flanking ducts 73 and 74, a large volume of air impinges downwardly against the tracks 83, into the trough areas thereof, causing good tractive contact of the tracks with the ground and holding the lower runs of the track 83 fairly level with the tangential track meeting peripheries of such wheels.

There are times when excessively dusty areas or terrain may be encountered by the machine or vehicle under air reactionary operation. Under such conditions, it may be desirable to use the auxiliary drive track assemblies. With the end duct flaps closed and the side ducts open, the air under pressure will react against the ground runs of the tracks, discharging upwardly out of the track troughs to considerably lessen dust churning and fanning conditions.

The foregoing description refers to certain'preferred embodiments of the invention by way of example only. Other applications are possible. It is contemplated that certain changes may be made in the elements shown or in the combinations presented without departing from the fundamental concept of the invention. The extent of such modifications shall, however, be governed by the breadth and scope of the language contained in the following claimed subject matter directed to the auxiliary propulsion means of the present invention.

What I claim is:

1. In a vehicle, in combination, a body providing an enclosed contour thereunder for over ground travel, trac tive units, elevating structures connected with said tractive units and adapted to raise and lower such units with respect to the body and in relation to the bottom of said body, said elevating structures being mounted upon said body at opposite sides thereof, actuating means connected with said elevating structure to move said tractive units between said raised and lowered positions, apparatus providing a source of compressed air, a first duct means connected with said source to direct air therefrom for discharge beneath said body to establish a cushion of pressurized air to float said body in a raised spaced relation with respect to said ground for travel thereover, said tractive units each comprising a tread member and a tread member supporting and guiding member including a second duct means connected with said air source and communicating with a given area lying between said members to permit passage of compressed air into said area to provide a cushion of compressed air therein to urge said members out of physical contact with respect to each other, said first duct means cooperating to support said body at a given level above the ground to permit free movement of said tractive units into positions beneath the level of the bottom of the body and free movement of the units upwardly therefrom and valve control means for each of the aforesaid duct means to selectively and independently deliver compressed air into the first duct means to cause said body to raise into a position above the ground thus elevating said tractive units therewith, or to transpose a cushion of compressed air between the members of the tractive unit when admitting air to said second duct means with the body lowered and supported through said tractive units upon the ground.

2. In a vehicle as in claim 1, including power transmission means connected to drive said tractive units to maneuver said body in predetermined directions.

3. In a vehicle as in claim 1, wherein said elevating structures comprise swingable mechanisms connected with said tractive units and with said body to permit bodily shifting of the units into said aforementioned elevated or lowered positions in relation to the body.

4. In a vehicle as in claim 3 wherein said actuating means each comprise power cylinders connected with said body and with the swingable mechanisms to bodily raise or lower said tractive units in relation to said body.

5. In a mobile vehicle having a source of air under pressure with conduit means to direct such air against a ground surface underlying the vehicle to create a sustaining air cushion to float said vehicle in spaced relation to the ground, in combination, air exhaust channel members communicating with said conduit means, control means to regulate the discharge of said air through said exhaust channel members, and an auxiliary vehicle drive mechanism comprising retractable ground engaging tracks, operable mechanisms carried upon said vehicle and connected with said tracks for actuation of the tracks between raised inoperative positions and lowered operative positions in direct contact with the ground surface and beneath the body of the vehicle, and actuating means on said vehicle connected with said operable mechanisms of the tracks to bodily move the tracks into said predetermined positions with the ground engaging portion of the tracks in the path of the air discharge area of certain of the exhaust channel members to permit the air therefrom to react against the adjacent upper surface of the track and to force the track firmly downwardly against the ground to enhance the tractive effort thereof during the period when the vehicle is rigged for travel by said retractable tracks.

6. In a mobile vehicle as in claim 5, wherein said tracks each comprise a flexible continuous belt structure looping over fore and aft wheels, said belt structure having a traction face with upstanding flanges thereon to form an elongated trough shaped traction member, said trough shaped portion lying inwardly of the looping belt structure forming means acting to reverse the flow of air directed against the ground engaging portion of said traction member when disposed in the path of the exhaust air.

7. A vehicle comprising, in combination, an air system on said vehicle comprising mechanism to establish a pressurized air cushion under said vehicle to render the same dirigible, conduit means connected with and arranged to channel the pressurized air from said system toward the ground at predetermined exhaust areas, tractive power means on said vehicle comprising track assemblies on opposite sides of the vehicle each having fore and aft spaced wheels and a looping traction belt passing thereover, and lift mechanisms operably mounted upon said vehicle and connected with each track assembly respectively, said lift mechanisms providing means to bodily guide the assemblies relatively to said vehicle from raised inoperative positions into lowered ground contacting positions to physically support said vehicle, and when in said lowered positions said track assemblies provide means to orient the ground contacting runs of said traction belts in positions beneath certain of said air exhaust areas to received air discharged from the vehicle air system upon said ground contacting runs to urge the latter firmly against the ground.

8. A vehicle as in claim 7 with the addition of air control mechanism connected with said air conduit means to selectively direct certain given portions of the vehicle air into the discharge areas overlying the adjacent ground contacting runs of the tract-ion belts.

9. In a vehicle equipped with an air system apparatus having air duct means arranged to establish a cushion of pressurized air between the under part of the vehicle and the ground to completely sustain and float said vehicle freely in an elevated spaced relation above the surface of the ground for airborne travel over generally level ground, an improvement comprising substitute auxiliary drive means for said air system apparatus carried by said vehicle for selective physical contact directly with the ground to mechanically support said vehicle and to propel the vehicle, and supporting mechanisms being mounted upon the vehicle to movably carry said auxiliary drive means comprising bearing units on said vehicle, bracket members operably connected with said bearing units for bodily swinging movement relatively to said vehicle, said bracket members vbeing connected with said drive means respectively to bodily swing the drive means from raised positions above the lower structural extremity of the vehicle to lowered positions lo cated lower than the lower structural extremity of the vehicle, said air system apparatus providing cooperative means to maintain the vehicle in an elevated airborne position sufliciently raised above the ground to provide the necessary clearance to permit bodily swinging of said drive means toward and away from their maximum lowered positions upon the ground below the lower structural extremities of the vehicle bottom, said drive means each comprising a track provided with a plenum member, a tread member entrained over said plenum member, and air conduit means to supply air under pressure from said air system apparatus to said plenum member, said plenum member having air vent apertures to direct air into an area interposed between said tread member and said plenum member to establish a cushion of air between said members to urge said members out of physical contact with respect to one another.

10. In a vehicle combination as in claim 9, wherein '7 cooperative air valving means are provided for said air duct means and for said conduit means of the plenum member to selectively out 01f air for said vehicle operation to bypass air under pressure through said air conduit means into the plenum member for dispersion into the area disposed between said tread and plenum memhers.

11. A mobile vehicle for travel over generally level .and inclined ground surface areas comprising, in combination, selectively operable mobile apparatus to support and provide the means to propel the vehicle over the ground areas, one portion of said apparatus comprising an air pressure system with air discharge means to establish a supporting cushion of air beneath the vehicle to sustain said vehicle for motion in a given raised 1 for the physical oif the ground support of said vehicle structure, said one air pressure portion of said apparatus being used for normal travel over generally level ground areas and said other drive mechanism portions of said apparatus being employed for travel over inclined ground areas, said one a-ir apparatus further providingan appropriate aircushio'n to maintain said vehicle at a given elevated position with respect to the lower structural limits thereof with the vehicle raised suificiently to permit the actuating means for said drive mechanisms to freely and bodily swing such mechanisms between the aforesaid raised inoperative and lowered ground contacting positions that are below the level of the lower limits of the vehicle structure; such drive mechanisms, when lowered, providing a substitute mechanical maneuverable means for the air cushion maneuverable means of the vehicle at such times when the latter encounters inclined ground terrain of a nature presenting topography to impede the progress of the vehicle when airborne, said mechanical drive mechanisms each including power driven ground supported track assemblies each having air entrappin'g surface portions subjected to air pressure to enhance the eflfective operation of the tracks, said one air apparatus portion providing the operative means whereby to supply air under pressure to the air entrapping portions of the track assemblies.

References Cited in the file of this patent UNITED STATES PATENTS 2,051,496 Sarrazin -Q Aug. 18, 1936 2,173,794 Von Radiis et al Sept. 19, 1939 2,953,320 Parry Sept. 20, 1960 2,969,032 Pinnes Jan. 24, 1961 FOREIGN PATENTS 219,133 Australia Jan. 8, 1959 OTHER REFERENCES Popular Science; July 1959; pages 51, 52, 53, 54, 55, 194; article entitled, Here Come Cars Without Wheels. 

11. A MOBILE VEHICLE FOR TRAVEL OVER GENERALLY LEVEL AND INCLINED GROUND SURFACE AREAS COMPRISING, IN COMBINATION, SELECTIVELY OPERABLE MOBILE APPARATUS TO SUPPORT AND PROVIDE THE MEANS TO PROPEL THE VEHICLE OVER THE GROUND AREAS, ONE PORTION OF SAID APPARATUS TO COMPRISING AN AIR PRESSURE SYSTEM WITH AIR DISCHARGE MEANS TO ESTABLISH A SUPPORTING CUSHION OF AIR BENEATH THE VEHICLE TO SUSTAIN SAID VEHICLE FOR MOTION IN A GIVEN RAISED POSITION ABOVE THE GROUND, ANOTHER PORTION OF SAID APPARTUS COMPRISING MECHANICAL DRIVE MECHANISMS FOR GROUND ENGAGEMENT MOUNTED UPON THE VEHICLE AND INCLUDING ACTUATION MEANS TO BODILY DISPLACE SUCH DRIVE MECHANISMS BETWEEN ELEVATED INOPERATIVE LOCATIONS SITUATED ABOVE THE LOWER STRUCTURAL LIMITS OF THE VEHICLE AND LOWERED GROUNG CONTACTING LOCATIONS WITH THE DRIVE MECHANISMS OCCUPYING MAXIMUM EFFECTIVE POSITIONS SPACED BELOW THE LOWER STRUCTURE LIMITS OF THE VEHICLE FOR THE PHYSICAL OFF THE GROUND SUPPORT OF SAID VEHICLE STRUCTURE, SAID ONE AIR PRESSURE PORTION OF SAID APPARATUS BEING USED FOR NORMAL TRAVEL OVER GENERALLY LEVEL GROUND AREAS AND SAID OTHER DRIVE MECHANISM PORTIONS OF SAID APPARATUS BEING EMPLOYED FOR TRAVEL OVER INCLINED GROUND AREAS, SAID ONE AIR APPARATUS FURTHER PROVIDING AN APPROPRIATE AIR CUSHION TO MAINTAIN SAID VEHICLE AT A GIVEN ELEVATED POSITION WITH RESPECT TO THE LOWER STRUCTURAL LIMITS THEREOF WITH THE VEHICLE RAISED SUFFICIENTLY TO PERMIT THE ACTUATING MEANS FOR SAID DRIVE MECHANISMS TO FREELY AND BODILY SWING SUCH MECHANISMS BETWEEN THE AFORESAID RAISED INOPERATIVE AND LOWERED GROUND CONTACTING POSITIONS THAT ARE BELOW THE LEVEL OF THE LOWER LIMITS OF THE VEHICLE STRUCTURE; SUCH DRIVE MECHANISMS, WHEN LOWERED, PROVIDING A SUBSTITUTE MECHANICAL MANEUVERABLE MEANS FOR THE AIR CUSHION MANEUVERABLE MEANS OF THE VEHICLE AT SUCH TIMES WHEN THE LATTER ENCOUNTERS INCLINED GROUND TERRAIN OF A NATURE PRESENTING TOPOGRAPHY TO IMPEDE THE PROGRESS OF THE VEHICLE WHEN AIRBORNE, SAID MECHANICAL DRIVE MECHANISMS EACH INCLUDING POWER DRIVEN GROUND SUPPORTED TRACK ASSEMBLIES EACH HAVING AIR ENTRAPPING SURFACE PORTIONS SUBJECTED TO AIR PRESSURE TO ENHANCE THE EFFECTIVE OPERATION OF THE TRACKS, SAID ONE AIR APPARATUS PORTION PROVIDING THE OPERATIVE MEANS WHEREBY TO SUPPLY AIR UNDER PRESSURE TO THE AIR ENTRAPPING PORTIONS OF THE TRACK ASSEMBLIES. 